or IVorked out by the late Dr Front. 101 



oily, and the albuminous, and likewise that the milk which 

 nature has provided for the support of the young in mammi- 

 ferous animals is alone capable of sustaining life, because it 

 contains all three. 



Thus, while the former inquiry of Dr Prout' s contains the 

 germ of one great principle so insisted upon by Liebig ; 

 namely, the necessity for those minute quantities of mineral 

 matters which are found to be present in plants, the latter 

 suggested the groundwork of the Baron's other great work, 

 in which he has explained so luminously the nature of the 

 proximate principles required for the nutrition, and for the 

 maintenance of heat, in animals. With regard to inquiries 

 more purely medical, Dr Prout first gave a clear idea of the 

 constitution of the urine, and shewed that the secretion of 

 urea took place in the bloodvessels, whilst it was merely 

 eliminated by the kidneys. By ascertaining that the urine 

 of reptiles consists wholly of uric acid, he took the first step 

 towards pointing out the relation between that body and 

 urea, which latter Liebig supposes to be produced in warm- 

 blooded animals, through the oxygenation of the former 

 compound. 



While by this train of research he threw so much impor- 

 tant light upon the physiology of calculus, and other urinary 

 disorders, he advanced at the same time our knowledge of 

 digestion itself, by his discovery that the stomach in a 

 healthy state always contains free muriatic acid. Hence 

 probably the necessity of salt for all the higher animals. 



Such are a few of the great principles, either suggested 

 or worked out by Dr Prout — contributions to physiological 

 science important enough to establish his reputation as a 

 great original thinker, as well as an accurate and scrupulous 

 experimentalist. His two principal publications, namely, 

 his Bridgewater Treatise and his work On the Stomach and 

 Urinary Diseases, are each characterised by a very high, 

 although a distinct order of merit. The former not only 

 evinces a thorough mastery of the details of his subject, but 

 also much ingenuity in unravelling the mysteries which beset 

 us when we attempt to speculate on the intimate constitution 



